RESUMO
SUMMARY: To establish an unprovable diagnostic indicative index reference for ultrasound examination of the fetal cerebral ventricles, based on the morphological characteristics throughout fetal nervous system development. Key ultrasonic morphological indicators of fetal ventricular development, which includes frontal horn width (FHW), occipital horn width (OHW), width of 3rd ventricle, cavity of septum pellucidum (CSP), width and length of 4th ventricle and thalamo-occipital distance (TOD) had been measured and analyzed collectively. All data of the indicators was collected on singleton pregnant woman between 16-39 weeks of gestational age (GA), between November 2017 and June 2021 at the Second Hospital of Dalian Medical University. A total of 235 pregnant women were enrolled in the cross section study; another 36 pregnant women voluntarily joined a timeline-tracking follow-up study (cohort study) under the same examining criteria. A decrease of FHW and OHW of the lateral ventricles was observed as GA increased; while dimensional values of TOD, 3rd ventricle, CSP, as well as 4th ventricle increased with GA. Most of these indicators showed an enhanced variation tendency within a certain period of GA. Moreover, values of FHW and TOD showed asymmetry of the two hemispheres within the whole GA. Our findings revealed the morphological regularity of fetal ventricular development, which would instructively enhance the relative clinical ultrasound diagnosis; moreover, TOD also showed regularly changes as GA increased, suggesting that TOD should be considered as an additional routine ultrasonic indicator for fetal ventricular development.
RESUMEN: El objetivo del estudio fue establecer un índice de referencia indicativo diagnóstico no demostrable para el examen ecográfico de los ventrículos cerebrales fetales, basado en las características morfológicas a lo largo del desarrollo del sistema nervioso fetal. Indicadores morfológicos ultrasónicos clave del desarrollo ventricular fetal, que incluyen el ancho del cuerno frontal (FHW), el ancho del cuerno occipital (OHW), el ancho del tercer ventrículo, la cavidad del septo pelúcido (CSP), el ancho y el largo del cuarto ventrículo y la distancia tálamo-occipital (TOD) fueron medidos y analizados conjuntamente. Todos los datos de los indicadores se recopilaron en mujeres embarazadas de un solo feto entre 16 y 39 semanas de edad gestacional (EG), entre noviembre de 2017 y junio de 2021 en el Segundo Hospital de la Universidad Médica de Dalian. Un total de 235 mujeres embarazadas se inscribieron en el estudio transversal; otras 36 mujeres embarazadas se unieron voluntariamente a un estudio de seguimiento de línea de tiempo (estudio de cohorte) bajo los mismos criterios de examen. Se observó una disminución de FHW y OHW de los ventrículos laterales a medida que aumentaba la GA; mientras que los valores dimensionales de TOD, tercer ventrículo, CSP y cuarto ventrículo aumentaron con GA. La mayoría de estos indicadores mostraron una tendencia de variación mejorada dentro de un cierto período de GA. Además, los valores de FHW y TOD mostraron asimetría de los dos hemisferios dentro de toda la AG. Nuestros hallazgos revelaron la regularidad morfológica del desarrollo ventricular fetal, lo que mejoraría de manera instructiva el diagnóstico clínico de ultrasonido relativo; además, TOD también mostró cambios regulares a medida que aumentaba la GA, lo que sugiere que TOD debe considerarse como un indicador ultrasónico de rutina adicional para el desarrollo ventricular fetal.
Assuntos
Humanos , Feminino , Gravidez , Ventrículos Cerebrais/crescimento & desenvolvimento , Ventrículos Cerebrais/diagnóstico por imagem , Ultrassonografia Pré-NatalRESUMO
O Cebus apella é uma espécie protegida por lei, contribui para a manutenção dos ecossistemas florestais com comportamento social semelhante aos humanos. Descrevemos a topografia das áreas cerebrais do Cebus apella, para observar e descrever a organização dos sulcos e lobos em cada hemisfério cerebral, esquematizando-os. A análise foi feita pela observação de 30 (trinta) hemisférios cerebrais, fixados em álcool 70 %, dissecados sob mesoscopia de luz. Foram descritos 4 (quatro) lobos cerebrais principais: Frontal; Parietal; Temporal e Occipital e suas complexas circunvoluções cerebrais, característica de primatas com movimentos rápidos. A análise foi: vista medial apresentando sulco caloso marginal, parieto-occipital, calcarino, para-calcarino, retro-calcarino, colateral, occipito-temporal e rostral; vista lateral apresentando sulco rectus, frontal médio, ramo horizontal arcuatus, superior subcentral, arcuatus, lateral, paralelo, temporal inferior, central, intraparietal, angular, pré-occipital transverso, occipital tranverso ou lunatus, occipital inferior, occipital médio, occipital superior e parieto-occipital. São constantes na vista lateral os sulcos lateral, paralelo, central, intraparietal e lunatus, os demais variam de um antímero para o outro. Na vista medial os sulcos parieto-occipital, caloso marginal e calcarino são constantes. Na morfologia dos giros cerebrais a presença ou ausência dos sulcos e suas variações são indicativos de uso maior ou menor de córtex cerebral, característica importante para o domínio das circunstâncias sociais e ambientais, para garantir a sobrevivência da espécie.
The Cebus is a species protected by law, which contributes to the maintenance of forest ecosystems, presenting a social behavior similar to humans. The brain area topography of Cebus is described in this paper, with the purpose of observing and describing the organization of the sulcus and lobes in each cerebral hemisphere, outlining them. The analysis was performed by observing thirty (30) cerebral hemispheres fixed in 70% alcohol, dissected under mesoscopy light. Four (4) major cerebral lobes have been described: Frontal; Parietal; Temporal and Occipital and their complex brain convolutions, characteristic of primates with rapid movements. The areas analyzed were: facies medialis showing marginal sulcus callosum, parietal-occipital, calcarinus, retro calcarinus, collaterales, occipital temporales and rostralis; facies lateralis showing sulcus rectus, medialis rostralis, horizontal arcuatus segment, superior sub-central, arcuatus, lateralis, parallel, inferior temporalis, centralis, intraparietalis, angular, transverse pre-occipital, tranverse occipital or lunatus, inferior occipital, medius occipital, superior occipital and parietalis occipital. The lateral view presented the lateral, parallel, central, intraparietal and lunatus sulcus, and the other ranged from one antimere to the other. The medialis view presented the parietal-occipital sulcus, marginal and calcarinus callosum. The morphology of the brain gyrus, the presence or absence of sulcus and their variations are an indication of greater or lower use of the brain cortex, an important characteristic for the domain of the social and environmental circumstances to guarantee the survival of the species.
Assuntos
Cebus , Cérebro/anatomia & histologiaRESUMO
Objetivo. Describir morfológica y morfométricamente el cerebro de tiburoncito Ariopsis seemanni. Materiales y métodos. Se trabajó con 10 ejemplares juveniles de tiburoncito los cuales fueron procesados con las normas éticas para el manejo de peces. Posteriormente se tomaron medidas de longitud total y estándar (cm) y de peso (g) de cada uno de los individuos, que se fijaron en formaldehido al 4%. Una vez retirados los encéfalos se realizó la identificación y medición de los diferentes lóbulos indicando su ubicación, morfología, longitud y área a través de imágenes laterales, dorsales y ventrales digitalizadas, las cuales fueron medidas con el programa Scion Image. Se calcularon promedios y desviaciones estándar, y se obtuvo la equivalencia porcentual de cada estructura en relación con la totalidad del encéfalo. Estos datos se relacionaron posteriormente con los hábitos de la especie. Resultados. Se identificaron los bulbos olfativos, hemisferios telencefálicos, lóbulos ópticos, cerebelo, entre otros. De los nervios craneales, únicamente se observó el nervio óptico. La estructura más grande del encéfalo es el cerebelo (44 ± 1,2 % y área 0,23 ± 0,03 cm²), seguido por los hemisferios telencefálicos (28 ± 0,57 % y área 0,13 ± 0,02 cm²). Conclusiones. La morfología del encéfalo de A. seemanni presentó el patrón general de teleósteos del orden Siluriforme, contando con el cerebelo como la estructura más grande. Según la morfología y morfometría vista en el encéfalo, se podría postular que A seemanni emplea sobre todo la vista y el gusto para explorar el ambiente.
Objective. To describe morphologically and morphometrically the encephalon of Ariopsis seemanni. Materials and methods. We worked with 10 juvenile specimens which were processed according to the ethical standards for handling fish. Measurements of the total and standard length (cm) and weight (g) were taken for each individual. Specimens were fixed in 4% formaldehyde. The encephalon was removed, the different regions were identified and the measurement of the different lobes was done, indicating their location, morphology, length and area using lateral, dorsal and ventral digitalized images that were measured with the Scion Image program. We calculated means and standard deviations, and obtained the percentage equivalence of each structure in relation to the entire encephalon. These data were then related to the habits of the species. Results. We identified the olfactory bulbs, telencephalic hemispheres, optic lobes, cerebellum, among others. Of the cranial nerves, only the optic nerve was observed. The largest structure of the encephalon is the cerebellum (44 ± 1.2% and 0.23 ± 0.03 cm² area), followed by the telencephalic hemispheres (28 ± 0.57% and 0.13 ± 0.02 cm² area). Conclusions. The encephalon morphology of A. seemanni presented the general pattern of teleosts of the order Siluriformes, with the cerebellum as the largest structure of the encephalon. Based on the morphology and morphometry observed in the encephalon, we suggest that A. seemanni uses primarily vision and taste to explore the environment.
Objetivo. Descrever os aspectos morfológicos e morfométricos do cérebro do peixe gato tete, Ariopsis seemanni. Materiais e métodos. A pesquisa foi realizada com 10 destes peixes, que foram tratados com as normas éticas para a manipulação de peixes. Posteriormente foram registrados o comprimento total e padrão (cm) e o peso (g) de cada um dos indivíduos, os quais foram fixados em formol 4%. Depois de retirar os encéfalos foi realizada a identificação e medição dos diferentes lóbulos, indicando sua localização, morfologia, o comprimento e a área através de imagens laterais, dorsais e ventrais digitalizadas, que foram medidas com o programa Scion Image. Foram calculados a média e o desvio padrão, e obteve-se a equivalência percentual de cada estrutura em relação a todo o encéfalo. Estes dados foram correlacionados com os hábitos da espécie. Resultados. Foram identificados os bulbos olfatórios, hemisférios telencefálico, lobos ópticos, cerebelo, entre outros. Dos nervos cranianos, apenas o nervo ótico foi observado. A maior estrutura do encéfalo é o cerebelo (44 ± 1,2% e 0,23 ± 0,03 cm² de área), seguido pelos hemisférios telencefálicos (28 ± 0,57% e área 0,13 ± 0,02 cm²). Conclusões. A morfologia do encéfalo de A. seemanni apresentou o padrão geral de teleósteos da ordem Siluriformes, com o cerebelo como a maior estrutura. De acordo com a morfologia e morfometria vista no encéfalo, pode-se postular que um A seemanni usa principalmente a visão e o gosto para explorar o ambiente.
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The DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders, fourth Edition, text Revision) defines attention-deficit/hyperactivity disorder (ADHD) as a disorder usually first diagnosed during infancy. Its essential feature is a persistent pattern of inattention and/or hyperactivity-impulsivity that is more frequent and severe than typically observed in individuals at a comparable level of development. It produces a significant impairment in social, academic, or occupational functioning. The prevalence of ADHD among the general population is between 5-10% in children and adolescents, and 1.2% to 7.3% in adults. In clinical samples, the prevalence in adults is higher: 1 6.80%. Less than 10% of the children diagnosed with ADHD reached a total functional remission when they became adults. Subjects with ADHD have a higher risk of suffering personality disorders and substance abuse. This disorder has a genetic basis. About 80% of the variance is explained by genetics. Some of the genes implied in this disorder are the dopamine transporter, the dopamine receptor 4, the beta-hydroxilase enzyme, the adrenergic receptor α2, the serotonin transporter and the serotonin receptor 1B. Environmental factors such as parental nicotine consumption during pregnancy, low birth weight, perinatal problems, parental psychiatric disorders, social adversity, and low parental education are related to a higher risk for ADHD. Several studies have shown that there are morphological brain abnormalities in subjects with ADHD. Structures like frontal lobe, cerebellar hemispheres and vermis, callosum splenium, cingulate anterior cortex and right caudate, are smaller in subjects with ADHD compared with healthy subjects. On the other hand, regarding the response to stimulants, studies with positron emission tomography (PET), among other techniques, suggest that the dopamine and noradrenergic systems play a role in the pathophysiology of ADHD. From 1990 to date, there are 41 morphological studies in ADHD, published in English, reporting volumetric abnormalities. However, the results are contradictory, so definitive conclusions about the brain structures being involved in ADHD remain unclear. Objective This article reviews the general neurobiology of ADHD providing an updated and comprehensive overview of the brain structural findings. The methodologies of morphological studies using magnetic resonance imaging (MRI) are reviewed in detail so as to find the source of the contradictory findings reported in the published studies. Method A literature search and review of the relevant published articles in MEDLINE and PsycINFO sites was made using the following key words: attention deficit hyperactivity disorder, neurobiology, morphological alteration, and MRI. In general, the literature supports the genetic basis of the disorder as well as the involvement of dopaminergic and noradrenergic systems in the pathophysiology. Nevertheless, regarding the structural abnormalities reported in ADHD, there is an enormously heterogeneous methodology in MRI scan acquisition and processing. Almost every study used a different image analysis to measure brain structures. Some works chose a hand user definition of the region of interest (ROI), which is prone to a user's bias. Other papers used a semi-automated analysis combining a user-defined ROI and segmentation techniques based only in intensity. These methodologies are prone to bias and to a deficient separation of grey and white matter. Finally, the automated methods where there is no user intervention are preferred because they are not a biased in the selection of ROI and use tissue probability maps to improve the segmentation. Unfortunately, none of these methods has been validated against histological and anatomopatological data. So, there is not a measure of validity and reliability of these methods. On the other hand, female subjects are extremely underrepresented in these studies: only around 20% of the individuals studied were females and only 50% of the ADHD samples included female subjects, whereas 95% included males. The number of reports done in ADHD adults is very scarce. Discussion Despite the multiple inconsistencies found in each MRI study as a consequence of limitations such as small samples size, and methodological differences across the studies such as lack of consistency in the acquisition and the image analysis, the structures more frequently and consistently reported to be smaller in ADHD subjects, compared to healthy subjects, are regions of the frontal lobe, the callosum splenium, the anterior cingulate gyrus, the vermis, the cerebral hemispheres and the right caudate. However, these findings are applicable to the most frequently studied samples: male children. Considering the prevalence and lack of complete remission of ADHD symptoms during adulthood, there is a need for structural studies in adults as well as in women. Conclusion The findings and results of MRI studies represent clear but insufficient advances in the knowledge of the anatomical structures involved in ADHD. There is a lack of research on the age-related changes imposed by neurodevelopment. The brain abnormalities and their gender differences in ADHD individual are subjects of future research.
El trastorno por déficit de atención e hiperactividad (TDAH) se caracteriza por un patrón persistente de inatención y/o hiperactividad e impulsividad y produce un deterioro en diversas áreas del funcionamiento del individuo. La prevalencia del TDAH en niños y adolescentes en la población general es de 5-10% y en adultos es de 1.2 a 7.3%. Menos del 10% de los niños que fueron diagnosticados con TDAH alcanzan una remisión funcional total en la edad adulta. Estos sujetos presentan más riesgo de sufrir un trastorno grave de la personalidad así como de dependencia a substancias. Cerca del 80% de la varianza del TDAH se explica por factores genéticos. Los genes que han sido asociados al TDAH con más frecuencia son aquellos que codifican al transportador de dopamina, al receptor de dopamina D4, a la enzima beta-hidroxilasa, al receptor adrenérgico a2, al transportador de serotonina y al receptor de serotonina 1B. Existen variables medioambientales asociadas al TDAH; como el consumo materno de tabaco durante el embarazo, las complicaciones perinatales, la psicopatología de los padres, y la adversidad psicosocial. Por otra parte, la respuesta a los estimulantes así como los estudios hechos con tomografía por emisión de positrones, sugieren que la dopamina y los sistemas noradrenérgicos tienen un papel en la fisiopatología del TDAH. Desde 1990 a la fecha, se han realizado 41 estudios morfológicos del TDAH que han reportado anormalidades volumétricas. Sin embargo, los resultados son contradictorios, lo que no permite obtener conclusiones definitivas acerca de las estructuras involucradas en el trastorno. Objetivo El presente artículo presenta una revisión general de la neurobiología del TDAH y una actualización de las anomalías estructurales encefálicas en los sujetos con TDAH por medio del uso de imágenes por resonancia magnética (IRM). Se han revisado en detalle las metodologías usadas en los estudios estructurales con el fin de conocer el origen de los hallazgos contradictorios en los estudios publicados hasta la fecha. Métodos Se realizó una búsqueda en la bibliografía médica de los artículos publicados en las bases MEDLINE y PsycINFO, con las siguientes palabras clave: TDAH, neurobiología, alteraciones morfológicas e imágenes por resonancia magnética. Resultados Los estudios sobre las anormalidades estructurales en el TDAH muestran una enorme heterogeneidad en la metodología de la adquisición y del procesamiento de las IRM. Por otro lado, la mayoría de los estudios se han realizado en niños del sexo masculino. Existen pocos artículos realizados en sujetos del sexo femenino y en adultos. Discusión A pesar de las inconsistencias encontradas en cada estudio de IRM, las estructuras encefálicas que se reportan reducidas en los sujetos TDAH son: el lóbulo frontal, el esplenio calloso, el cíngulo anterior, el vermis cerebeloso, los hemisferios del cerebelo y el núcleo caudado derecho. Dada la alta prevalencia del TDAH y la falta de remisión de síntomas en la población adulta, es necesario realizar más estudios estructurales en sujetos adultos y femeninos. Conclusión Los resultados obtenidos en los estudios de IRM constituyen avances claros pero insuficientes en el conocimiento de las estructuras anatómicas involucradas en el TDAH. Las anormalidades encefálicas entre los sujetos TDAH y las diferencias de edad y género entre estos sujetos deben ser los objetivos de futuras investigaciones.